1. Field of the Invention
Methods and apparatuses consistent with the present invention relate to a method and apparatus for compensating an amplitude clipping distortion and sequentially reconstructing a transmitted signal. More particularly, the present invention relates to a method and apparatus which Space-Time block codes or Space-Frequency block codes data, modulates the data using an orthogonal frequency division multiplexing (OFDM) scheme, receives a signal, which is amplitude-clipped and transmitted via a plurality of antennas, and thereby may sequentially reconstruct a transmitted signal from the amplitude clipping distortion.
2. Description of Related Art
In a wireless mobile communication, a wireless channel between a transmission apparatus and a receiving apparatus varies over time due to a fading phenomenon. A data transmission efficiency from a transmission apparatus to a receiving apparatus depends on a state of wireless channel. A transmission diversity method has been used to overcome a low data transmission efficiency due to a fading phenomenon.
The transmission diversity method transmits data, orthogonal to each other, using a plurality of antennas in a transmission apparatus, receives a signal using an orthogonality of signals transmitted from each of the plurality of antennas in a receiving apparatus, and thereby may maintain a data transmission efficiency even when a state of the wireless channel is deteriorated.
An orthogonal coding is used to transmit data, orthogonal to each other, using a plurality of antennas. The orthogonal coding generates a plurality of data streams, orthogonal to each other, from a single data stream, similar to a Space-Time block coding or a Space-Frequency block coding.
A multi-carrier transmission method such as an orthogonal frequency division multiplexing (OFDM) scheme or filtered multi-tone (FMT) is superior to a channel environment such as a frequency selective fading, narrowband interference, and the like. However, a power efficiency of a transmission amplifier decreases due to a high Peak-to-average power ratio (PAPR) and a nonlinear distortion of transmission signal may occur.
An amplitude clipping method from among PAPR reduction methods clips a portion of a level of an input signal, that is, the portion being greater than a reference value. The amplitude clipping method is easily and simply embodied. However, an amplitude clipping causes a distortion of transmission signal and degrades a bit-error rate (BER) of system.
Thus, a wireless data transmission apparatus and method and a wireless data receiving apparatus and method are required.